Add support for Elasticsearch 5.x

* Use log4j2.properties instead of logging.yml
* Add jvm.options
* Use bootstrap.memory_lock instead of bootstrap.mlockall
* Get rid of work directory
* Executable does not accept `-D` anymore, replace with `-E` and `-p`
* Get rid of 5.x default (file)s

templates/elasticsearch.yml.j2

@@ -18,6 +18,8 @@ path.conf: {{ conf_dir }}
 
 path.data: {{ data_dirs | array_to_str }}
 
+{% if es_version | version_compare('2.0', '<=') %}
 path.work: {{ work_dir }}
+{% endif %}
 
 path.logs: {{ log_dir }}